1. Field of the Invention
The invention relates to a connector to enhance a locking force of a lock.
2. Description of the Related Art
U.S. Pat. No. 5,235,743 discloses a connector with a housing that has a cavity and a lock that cantilevers forwardly from a side wall of the cavity. A terminal fitting is inserted into the cavity from behind and resiliently deforms the lock. The lock is restored resiliently and engages the terminal fitting when the terminal fitting is inserted sufficiently. Thus, the lock prevents the terminal fitting from coming out.
There have demands to miniaturize connectors in recent years and, accordingly, terminal fittings and cavities are formed smaller. As a result, locks have been formed narrower. There is a possibility that a narrower lock will deform relatively easily and buckle or break due to a pulling force on the wire and the terminal fitting.
In view of the above problem, an object of the invention is to enhance a locking force of a lock.
The invention is a connector with a housing and at least one cavity in the housing. A lock cantilevers from a side wall of the cavity. A terminal fitting is insertable into the cavity from behind and deforms the lock. However, the lock then is restored resiliently to engage the terminal fitting when the terminal fitting is inserted by a specified distance. The lock comprises a deformation permitting portion for permitting a resilient deformation such that the length of the lock becomes shorter or the lock undergoes a buckling or deforming motion when a compressive force acts on the lock along a direction substantially opposite to the inserting direction.
A force may act on the terminal fitting in a withdrawing direction while the terminal fitting is engaged with the lock. Thus, a compressive force acts on the lock substantially in the longitudinal direction. However, the lock undergoes a resilient deformation so that the lock becomes shorter by a function of the deformation permitting portion. Buckling strength is enhanced by as much as the lock is shortened and, as a result, a force for locking the terminal fitting is enhanced. This is suitable in miniaturizing the connector.
The lock preferably is restored so the leading end of the lock engages and locks the terminal fitting.
The deformation permitting portion preferably comprises a thinner portion at a selected location along the longitudinal direction of the lock.
The lock bends at the thinner portion when the compressive force acts substantially along the longitudinal direction of the lock. As a result, the lock is deformed resiliently to become shorter.
A locking projection preferably is formed on a side of the terminal fitting substantially facing the lock to increase an area of engagement with the lock. The lock preferably is recessed to form an insertion groove that permits the passage of the locking projection when the terminal fitting is inserted and resiliently deforms the lock. The deformation permitting portion is formed by making the insertion groove deeper at one part along the longitudinal direction.
The lock bends at the deeper part of the insertion groove when the compressive force acts on the lock in the longitudinal direction. Thus, the lock deforms resiliently and becomes shorter.
The insertion groove may be formed deeper by setting an inclination of a bottom of the insertion groove slightly steeper than that of a surface of the lock substantially opposite to the surface where the insertion groove is formed.
The deformation permitting portion preferably comprises a portion having a reduced cross-sectional area.
The deformation permitting portion preferably is at a base of the lock where the lock projects from the side wall substantially in the inserting direction.
A bent portion of the deformation permitting portion preferably contacts a corresponding portion of the side wall so as to strut the lock thereon when a compressive force acts on the lock substantially along the longitudinal direction. Accordingly, a locking force of the lock can be displayed reliably and enhanced.
The terminal fitting preferably is formed at a wall substantially facing the lock with a cut-away portion for engaging the lock. Sections of the wall before and behind the cut-away portion are coupled via a coupling portion at one side of the wall and the lock comprises an escaping portion for the coupling portion.
These and other features and advantages of the invention will become more apparent upon reading of the detailed description of preferred embodiments and the drawings. Even though embodiments are described separately, single features may be combined to additional embodiments.